Systems and methods for visualizing and programming electrical stimulation

ABSTRACT

Methods and systems can facilitate visualizing cathodic and anodic stimulation separately. Alternately, the methods and systems may separately visualize stimulation of different neural elements, such as nerve fibers and neural cells. These methods and systems can further facilitate programming an electrical stimulation system for stimulating patient tissue.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.16/396,285, filed Apr. 26, 2019, which claims the benefit under 35U.S.C. § 119(e) of U.S. Provisional Patent Application Ser. No.62/663,895, filed Apr. 27, 2018, both of which are incorporated hereinby reference.

FIELD

The present disclosure is directed to the area of implantable electricalstimulation systems and methods of making and using the systems. Thepresent disclosure is also directed to systems and methods forvisualizing stimulation or for programming an electrical stimulationsystem.

BACKGROUND

Implantable electrical stimulation systems have proven therapeutic in avariety of diseases and disorders. For example, spinal cord stimulationsystems have been used as a therapeutic modality for the treatment ofchronic pain syndromes. Peripheral nerve stimulation has been used totreat chronic pain syndrome and incontinence, with a number of otherapplications under investigation. Functional electrical stimulationsystems have been applied to restore some functionality to paralyzedextremities in spinal cord injury patients. Stimulation of the brain,such as deep brain stimulation, can be used to treat a variety ofdiseases or disorders.

Stimulators have been developed to provide therapy for a variety oftreatments. A stimulator can include a control module (with a pulsegenerator), one or more leads, and an array of stimulator electrodes oneach lead. The stimulator electrodes are in contact with or near thenerves, muscles, or other tissue to be stimulated. The pulse generatorin the control module generates electrical pulses that are delivered bythe electrodes to body tissue.

BRIEF SUMMARY

One aspect is a system for programming electrical stimulation of apatient using an implantable electrical stimulation system including animplantable pulse generator and a lead having a plurality of electrodes.The system includes a processor configured to obtain a cathodic volumeof activation (“VOA’) for at least one cathode, wherein the cathodic VOAis an estimated volume of tissue activated by the at least one cathodeusing a set of stimulation parameters; obtain an anodic VOA for at leastone anode, wherein the anodic VOA is an estimated volume of tissueactivated by the at least one anode using a set of stimulationparameters; and determine to display a graphical representation of theelectrodes, a graphical representation of the cathodic VOA, and agraphical representation the anodic VOA. Optionally, the processor isalso configured to, when the cathodic VOA or anodic VOA is modifiedusing modification controls, modify the graphical representation of thecathodic VOA or anodic VOA and determine a modified set of stimulationparameters corresponding to the modified cathodic VOA or anodic VOA;receive direction to program the implantable pulse generator with theset of stimulation parameters or modified set of stimulation parameters;and initiate a signal that provides the implantable pulse generator ofthe electrical stimulation system with the selected one of the set ofstimulation parameters or modified set of stimulation parameters forgenerating electrical stimulation for the patient through the electrodesof the lead.

Another aspect is a method for programming electrical stimulation of apatient using an implantable electrical stimulation system including animplantable pulse generator and a lead having a plurality of electrodes.The method includes obtaining a cathodic volume of activation (“VOA’)for at least one cathode, wherein the cathodic VOA is an estimatedvolume of tissue activated by the at least one cathode using a set ofstimulation parameters; obtaining an anodic VOA for at least one anode,wherein the anodic VOA is an estimated volume of tissue activated by theat least one anode using a set of stimulation parameters; anddetermining to display a graphical representation of the electrodes, agraphical representation of the cathodic VOA, and a graphicalrepresentation the anodic VOA. Optionally, the method also includes,when the cathodic VOA or anodic VOA is modified using modificationcontrols, modifying the graphical representation of the cathodic VOA oranodic VOA and determining a modified set of stimulation parameterscorresponding to the modified cathodic VOA or anodic VOA; receivingdirection to program the implantable pulse generator with the set ofstimulation parameters or modified set of stimulation parameters; andinitiating a signal that provides the implantable pulse generator of theelectrical stimulation system with the selected one of the set ofstimulation parameters or modified set of stimulation parameters forgenerating electrical stimulation for the patient through the electrodesof the lead.

A further aspect is non-transitory computer-readable medium havingcomputer executable instructions stored thereon that, when executed by aprocessor, cause the processor to perform the method describe above.

In at least some aspects, the processor is further configured to, or themethod further includes a step to, determine to display controls forturning off the display of the graphical representation of the cathodicVOA or the graphical representation of the anodic VOA. In at least someaspects, determining to display the graphical representation of thecathodic VOA and the graphical representation of the anodic VOA includesdetermining to display the graphical representation of the cathodic VOAfor regions that are closer to any one of the at least one cathode thanto any one of the at least one anode and determining to display thegraphical representation of the anodic VOA for regions that are closerto any one of the at least one anode than to any one of the at least onecathode.

In at least some aspects, determining to display the graphicalrepresentation of the cathodic VOA and the graphical representation ofthe anodic VOA includes using different graphical features todistinguish the graphical representation of the cathodic VOA and thegraphical representation of the anodic VOA. In at least some aspects,using different graphical features includes using a third graphicalfeature for any region in which the cathodic VOA overlaps the anodicVOA.

In at least some aspects, the modification controls include movecontrols to move the cathodic VOA or anodic VOA relative to the lead. Inat least some aspects, the modification controls include stretch orcompress controls to stretch or compress the cathodic VOA or anodic VOA.In at least some aspects, the processor is further configured todetermine to display a control for presenting an animation of a VOA fora time-varying stimulation.

In at least some aspects, obtaining the cathodic VOA includes obtainingcathodic VOAs for a plurality of different stimulation sets; obtainingthe anodic VOA includes obtaining anodic VOAs for the plurality ofdifferent stimulation sets; and determining to display the graphicalrepresentation of the cathodic VOA and the graphical representation ofthe anodic VOA includes determining to display the cathodic VOAs as aset of contour lines and the anodic VOAs as a set of contour lines.

In at least some aspects, obtaining the cathodic VOA includes obtainingcathodic VOAs for a plurality of different stimulation sets; obtainingthe anodic VOA includes obtaining anodic VOAs for the plurality ofdifferent stimulation sets; and determining to display the graphicalrepresentation of the cathodic VOA and the graphical representation ofthe anodic VOA includes determining to display the cathodic VOAs using afirst variation in shading or color and the anodic VOAs using a secondvariation in shading or color.

Another aspect is a system for programming electrical stimulation of apatient using an implantable electrical stimulation system including animplantable pulse generator and a lead having a plurality of electrodes.The system includes a processor configured to obtain a fiber volume ofactivation (“VOA’) for a set of stimulation parameters, wherein thefiber VOA is an estimated volume of tissue in which nerve fibers areactivated using the set of stimulation parameters; obtain a cell VOA fora set of stimulation parameters, wherein the cell VOA is an estimatedvolume of tissue in which neural cells are activated using the set ofstimulation parameters; and determine to display a graphicalrepresentation of the electrodes, a graphical representation of thefiber VOA, and a graphical representation the cell VOA. Optionally, theprocessor is further configured to, when the fiber VOA or cell VOA ismodified using modification controls, modify the graphicalrepresentation of the fiber VOA or cell VOA and determine a modified setof stimulation parameters corresponding to the modified fiber VOA orcell VOA; receive direction to program the implantable pulse generatorwith the set of stimulation parameters or modified set of stimulationparameters; and initiate a signal that provides the implantable pulsegenerator of the electrical stimulation system with the set ofstimulation parameters or modified set of stimulation parameters forgenerating electrical stimulation for the patient through the electrodesof the lead.

Yet another aspect is a method for programming electrical stimulation ofa patient using an implantable electrical stimulation system includingan implantable pulse generator and a lead having a plurality ofelectrodes. The method includes obtaining a fiber volume of activation(“VOA’) for a set of stimulation parameters, wherein the fiber VOA is anestimated volume of tissue in which nerve fibers are activated using theset of stimulation parameters; obtaining a cell VOA for a set ofstimulation parameters, wherein the cell VOA is an estimated volume oftissue in which neural cells are activated using the set of stimulationparameters; and determining to display a graphical representation of theelectrodes, a graphical representation of the fiber VOA, and a graphicalrepresentation the cell VOA. Optionally, the method further includes,when the fiber VOA or cell VOA is modified using modification controls,modifying the graphical representation of the fiber VOA or cell VOA anddetermining a modified set of stimulation parameters corresponding tothe modified fiber VOA or cell VOA; receiving direction to program theimplantable pulse generator with the set of stimulation parameters ormodified set of stimulation parameters; and initiating a signal thatprovides the implantable pulse generator of the electrical stimulationsystem with the set of stimulation parameters or modified set ofstimulation parameters for generating electrical stimulation for thepatient through the electrodes of the lead.

A further aspect is non-transitory computer-readable medium havingcomputer executable instructions stored thereon that, when executed by aprocessor, cause the processor to perform the method describe above.

In at least some aspects, obtaining the fiber VOA includes obtainingfiber VOAs for a plurality of different stimulation sets; obtaining thecell VOA includes obtaining cell VOAs for the plurality of differentstimulation sets; and determining to display the graphicalrepresentation of the fiber VOA and the graphical representation of thecell VOA includes determining to display the fiber VOAs as a set ofcontour lines and the cell VOAs as a set of contour lines.

In at least some aspects, obtaining the fiber VOA includes obtainingfiber VOAs for a plurality of different stimulation sets; obtaining thecell VOA includes obtaining cell VOAs for the plurality of differentstimulation sets; and determining to display the graphicalrepresentation of the fiber VOA and the graphical representation of thecell VOA includes determining to display the fiber VOAs using a firstvariation in shading or color and the cell VOAs using a second variationin shading or color.

In at least some aspects, determining to display the graphicalrepresentation of the fiber VOA and the graphical representation of thecell VOA includes using different graphical features to distinguish thegraphical representation of the fiber VOA and the graphicalrepresentation of the cell VOA. In at least some aspects, usingdifferent graphical features includes using a third graphical featurefor any region in which the fiber VOA overlaps the cell VOA.

In at least some aspects, the modification controls include movecontrols to move the fiber VOA or cell VOA relative to the lead. In atleast some aspects, the modification controls include stretch orcompress controls to stretch or compress the fiber VOA or cell VOA. Inat least some aspects, the processor is further configured to determineto display a control for presenting an animation of a VOA for atime-varying stimulation. In at least some aspects, the processor isfurther configured to, or the method further includes a step to,determine to display controls for turning off the display of thegraphical representation of the fiber VOA or the graphicalrepresentation of the cell VOA. In at least some aspects, determining todisplay the graphical representation of the fiber VOA and the graphicalrepresentation of the cell VOA includes using different graphicalfeatures to distinguish the graphical representation of the fiber VOAand the graphical representation of the cell VOA

Yet another aspect is a system for programming electrical stimulation ofa patient using an implantable electrical stimulation system includingan implantable pulse generator and a lead having a plurality ofelectrodes. The system includes a processor configured to determinewhich of a plurality of anatomical elements are activated by a thresholdamount by cathodic stimulation or anodic stimulation using a set ofstimulation parameters; and determine to display a graphicalrepresentation of the electrodes and graphical representation of theanatomical elements, indicating which of the anatomical elements areactivated by a threshold amount by cathodic stimulation, which of theanatomical elements are activated by a threshold amount by anodicstimulation, and which of the anatomical elements are not activated.Optionally, the processor is further configured to, when the set ofstimulation parameters is modified using modification controls,determine which of the anatomical elements are activated by a thresholdamount by cathodic stimulation or anodic stimulation using the modifiedset of stimulation parameters and modify the graphical representationsof the anatomical elements; receive direction to program the implantablepulse generator with the set of stimulation parameters or modified setof stimulation parameters; and initiate a signal that provides theimplantable pulse generator of the electrical stimulation system withthe set of stimulation parameters or modified set of stimulationparameters for generating electrical stimulation for the patient throughthe electrodes of the lead.

Another aspect is a method for programming electrical stimulation of apatient using an implantable electrical stimulation system including animplantable pulse generator and a lead having a plurality of electrodes.The method includes determining which of a plurality of anatomicalelements are activated by a threshold amount by cathodic stimulation oranodic stimulation using the set of stimulation parameters; anddetermining to display a graphical representation of the electrodes andgraphical representation of the anatomical elements, indicating which ofthe anatomical elements are activated by a threshold amount by cathodicstimulation, which of the anatomical elements are activated by athreshold amount by anodic stimulation, and which of the anatomicalelements are not activated. Optionally, the method also includes, whenthe set of stimulation parameters is modified using modificationcontrols, determining which of the anatomical elements are activated bya threshold amount by cathodic stimulation or anodic stimulation usingthe modified set of stimulation parameters and modifying the graphicalrepresentations of the anatomical elements; receiving direction toprogram the implantable pulse generator with the set of stimulationparameters or modified set of stimulation parameters; and initiating asignal that provides the implantable pulse generator of the electricalstimulation system with the set of stimulation parameters or modifiedset of stimulation parameters for generating electrical stimulation forthe patient through the electrodes of the lead.

A further aspect is non-transitory computer-readable medium havingcomputer executable instructions stored thereon that, when executed by aprocessor, cause the processor to perform the method describe above.

In at least some aspects, determining to display the graphicalrepresentation of the anatomical elements includes using differentgraphical features to distinguish the graphical representation of theanatomical elements activated by cathodic stimulation and the graphicalrepresentation of the anatomical elements activated by anodicstimulation.

BRIEF DESCRIPTION OF THE DRAWINGS

Non-limiting and non-exhaustive embodiments of the present invention aredescribed with reference to the following drawings. In the drawings,like reference numerals refer to like parts throughout the variousfigures unless otherwise specified.

For a better understanding of the present invention, reference will bemade to the following Detailed Description, which is to be read inassociation with the accompanying drawings, wherein:

FIG. 1 is a schematic view of one embodiment of an electricalstimulation system;

FIG. 2 is a schematic side view of one embodiment of an electricalstimulation lead;

FIG. 3 is a schematic block diagram of one embodiment of a system fordetermining stimulation parameters;

FIG. 4 is one embodiment of a user interface for visualizing cathodicand anodic stimulation;

FIG. 5 is another embodiment of a user interface for visualizingcathodic and anodic stimulation;

FIG. 6 is one embodiment of a user interface for visualizing fiber andcell stimulation;

FIG. 7 is another embodiment of a user interface for visualizing fiberand cell stimulation;

FIG. 8 is one embodiment of a user interface for visualizing anatomicalelement stimulation;

FIG. 9 is a flowchart of a first embodiment of a method of visualizingstimulation or for programming an electrical stimulation system;

FIG. 10 is a flowchart of a second embodiment of a method of visualizingstimulation or for programming an electrical stimulation system; and

FIG. 11 is a flowchart of a third embodiment of a method of visualizingstimulation or for programming an electrical stimulation system.

DETAILED DESCRIPTION

The present disclosure is directed to the area of implantable electricalstimulation systems and methods of making and using the systems. Thepresent disclosure is also directed to systems and methods forvisualizing stimulation or for programming an electrical stimulationsystem.

Suitable implantable electrical stimulation systems include, but are notlimited to, a least one lead with one or more electrodes disposed on adistal end of the lead and one or more terminals disposed on one or moreproximal ends of the lead. Leads include, for example, percutaneousleads, paddle leads, cuff leads, or any other arrangement of electrodeson a lead. Examples of electrical stimulation systems with leads arefound in, for example, U.S. Pat. Nos. 6,181,969; 6,516,227; 6,609,029;6,609,032; 6,741,892; 7,244,150; 7,450,997; 7,672,734; 7,761,165;7,783,359; 7,792,590; 7,809,446; 7,949,395; 7,974,706; 8,175,710;8,224,450; 8,271,094; 8,295,944; 8,364,278; 8,391,985; and 8,688,235;and U.S. Patent Applications Publication Nos. 2007/0150036;2009/0187222; 2009/0276021; 2010/0076535;

2010/0268298; 2011/0005069; 2011/0004267; 2011/0078900; 2011/0130817;2011/0130818; 2011/0238129; 2011/0313500; 2012/0016378; 2012/0046710;2012/0071949; 2012/0165911; 2012/0197375; 2012/0203316; 2012/0203320;2012/0203321; 2012/0316615; 2013/0105071; and 2013/0197602, all of whichare incorporated by reference. In the discussion below, a percutaneouslead will be exemplified, but it will be understood that the methods andsystems described herein are also applicable to paddle leads and otherleads.

A percutaneous lead for electrical stimulation (for example, deep brainor spinal cord stimulation) includes stimulation electrodes that can bering electrodes, segmented electrodes that extend only partially aroundthe circumference of the lead, or any other type of electrode, or anycombination thereof. The segmented electrodes can be provided in sets ofelectrodes, with each set having electrodes circumferentiallydistributed about the lead at a particular longitudinal position. Forillustrative purposes, the leads are described herein relative to usefor deep brain stimulation, but it will be understood that any of theleads can be used for applications other than deep brain stimulation,including spinal cord stimulation, peripheral nerve stimulation, orstimulation of other nerves, muscles, and tissues. In particular,stimulation may stimulate specific targets. Examples of such targetsinclude, but are not limited to, the subthalamic nucleus (STN), internalsegment of the globus pallidus (GPi), external segment of the globuspallidus (GPe), and the like. In at least some embodiments, ananatomical structure is defined by its physical structure and aphysiological target is defined by its functional attributes. In atleast one of the various embodiments, the lead may be positioned atleast partially within the target, but in other embodiments, the leadmay be near, but not inside, the target.

Turning to FIG. 1, one embodiment of an electrical stimulation system 10includes one or more stimulation leads 12 and an implantable pulsegenerator (IPG) 14. The system 10 can also include one or more of anexternal remote control (RC) 16, a clinician's programmer (CP) 18, anexternal trial stimulator (ETS) 20, or an external charger 22.

The IPG 14 is physically connected, optionally via one or more leadextensions 24, to the stimulation lead(s) 12. Each lead carries multipleelectrodes 26 arranged in an array. The IPG 14 includes pulse generationcircuitry that delivers electrical stimulation energy in the form of,for example, a pulsed electrical waveform (i.e., a temporal series ofelectrical pulses) to the electrode array 26 in accordance with a set ofstimulation parameters. The IPG 14 can be implanted into a patient'sbody, for example, below the patient's clavicle area or within thepatient's buttocks or abdominal cavity. The IPG 14 can have eightstimulation channels which may be independently programmable to controlthe magnitude of the current stimulus from each channel. In at leastsome embodiments, the IPG 14 can have more or fewer than eightstimulation channels (for example, 4-, 6-, 16-, 32-, or more stimulationchannels). The IPG 14 can have one, two, three, four, or more connectorports, for receiving the terminals of the leads.

The ETS 20 may also be physically connected, optionally via thepercutaneous lead extensions 28 and external cable 30, to thestimulation leads 12. The ETS 20, which may have similar pulsegeneration circuitry as the IPG 14, also delivers electrical stimulationenergy in the form of, for example, a pulsed electrical waveform to theelectrode array 26 in accordance with a set of stimulation parameters.One difference between the ETS 20 and the IPG 14 is that the ETS 20 isoften a non-implantable device that is used on a trial basis after theneurostimulation leads 12 have been implanted and prior to implantationof the IPG 14, to test the responsiveness of the stimulation that is tobe provided. Any functions described herein with respect to the IPG 14can likewise be performed with respect to the ETS 20.

The RC 16 may be used to telemetrically communicate with or control theIPG 14 or ETS 20 via a uni- or bi-directional wireless communicationslink 32. Once the IPG 14 and neurostimulation leads 12 are implanted,the RC 16 may be used to telemetrically communicate with or control theIPG 14 via a uni- or bi-directional communications link 34. Suchcommunication or control allows the IPG 14 to be turned on or off and tobe programmed with different stimulation parameter sets. The IPG 14 mayalso be operated to modify the programmed stimulation parameters toactively control the characteristics of the electrical stimulationenergy output by the IPG 14. The CP 18 allows a user, such as aclinician, the ability to program stimulation parameters for the IPG 14and ETS 20 in the operating room and in follow-up sessions.

The CP 18 may perform this function by indirectly communicating with theIPG 14 or ETS 20, through the RC 16, via a wireless communications link36. Alternatively, the CP 18 may directly communicate with the IPG 14 orETS 20 via a wireless communications link (not shown). The stimulationparameters provided by the CP 18 are also used to program the RC 16, sothat the stimulation parameters can be subsequently modified byoperation of the RC 16 in a stand-alone mode (i.e., without theassistance of the CP 18).

For purposes of brevity, the details of the RC 16, CP 18, ETS 20, andexternal charger 22 will not be further described herein. Details ofexemplary embodiments of these devices are disclosed in U.S. Pat. No.6,895,280, which is expressly incorporated herein by reference. Otherexamples of electrical stimulation systems can be found at U.S. Pat.Nos. 6,181,969; 6,516,227; 6,609,029; 6,609,032; 6,741,892; 7,949,395;7,244,150; 7,672,734; and 7,761,165; 7,974,706; 8,175,710; 8,224,450;and 8,364,278; and U.S. Patent Application Publication No. 2007/0150036,as well as the other references cited above, all of which areincorporated by reference.

FIG. 2 illustrates one embodiment of a lead 100 with electrodes 125disposed at least partially about a circumference of the lead 100 alonga distal end portion of the lead 100 and terminals 135 disposed along aproximal end portion of the lead 100. The lead 100 can be implanted nearor within the desired portion of the body to be stimulated such as, forexample, the brain, spinal cord, or other body organs or tissues. In oneexample of operation for deep brain stimulation, access to the desiredposition in the brain can be accomplished by drilling a hole in thepatient's skull or cranium with a cranial drill (commonly referred to asa burr), and coagulating and incising the dura mater, or brain covering.The lead 100 can be inserted into the cranium and brain tissue with theassistance of a stylet (not shown). The lead 100 can be guided to thetarget location within the brain using, for example, a stereotacticframe and a microdrive motor system. In at least some embodiments, themicrodrive motor system can be fully or partially automatic. Themicrodrive motor system may be configured to perform one or more thefollowing actions (alone or in combination): insert the lead 100,advance the lead 100, retract the lead 100, or rotate the lead 100.

In at least some embodiments, measurement devices coupled to the musclesor other tissues stimulated by the target neurons, or a unit responsiveto the patient or clinician, can be coupled to the IPG 14 or microdrivemotor system. The measurement device, user, or clinician can indicate aresponse by the target muscles or other tissues to the stimulation orrecording electrode(s) to further identify the target neurons andfacilitate positioning of the stimulation electrode(s). For example, ifthe target neurons are directed to a muscle experiencing tremors, ameasurement device can be used to observe the muscle and indicatechanges in, for example, tremor frequency or amplitude in response tostimulation of neurons. Alternatively, the patient or clinician canobserve the muscle and provide feedback.

The lead 100 for deep brain stimulation can include stimulationelectrodes, recording electrodes, or both. In at least some embodiments,the lead 100 is rotatable so that the stimulation electrodes can bealigned with the target neurons after the neurons have been locatedusing the recording electrodes.

Stimulation electrodes may be disposed on the circumference of the lead100 to stimulate the target neurons. Stimulation electrodes may bering-shaped so that current projects from each electrode equally inevery direction from the position of the electrode along a length of thelead 100. In the embodiment of FIG. 2, two of the electrodes 125 arering electrodes 120. Ring electrodes typically do not enable stimuluscurrent to be directed from only a limited angular range around a lead.Segmented electrodes 130, however, can be used to direct stimuluscurrent to a selected angular range around a lead. When segmentedelectrodes are used in conjunction with an implantable pulse generatorthat delivers constant current stimulus, current steering can beachieved to more precisely deliver the stimulus to a position around anaxis of a lead (i.e., radial positioning around the axis of a lead). Toachieve current steering, segmented electrodes can be utilized inaddition to, or as an alternative to, ring electrodes.

The lead 100 includes a lead body 110, terminals 135, one or more ringelectrodes 120, and one or more sets of segmented electrodes 130 (or anyother combination of electrodes). The lead body 110 can be formed of abiocompatible, non-conducting material such as, for example, a polymericmaterial. Suitable polymeric materials include, but are not limited to,silicone, polyurethane, polyurea, polyurethane-urea, polyethylene, orthe like. Once implanted in the body, the lead 100 may be in contactwith body tissue for extended periods of time. In at least someembodiments, the lead 100 has a cross-sectional diameter of no more than1.5 mm and may be in the range of 0.5 to 1.5 mm. In at least someembodiments, the lead 100 has a length of at least 10 cm and the lengthof the lead 100 may be in the range of 10 to 70 cm.

The electrodes 125 can be made using a metal, alloy, conductive oxide,or any other suitable conductive biocompatible material. Examples ofsuitable materials include, but are not limited to, platinum, platinumiridium alloy, iridium, titanium, tungsten, palladium, palladiumrhodium, or the like. Preferably, the electrodes 125 are made of amaterial that is biocompatible and does not substantially corrode underexpected operating conditions in the operating environment for theexpected duration of use.

Each of the electrodes 125 can either be used or unused (OFF). When anelectrode is used, the electrode can be used as an anode or cathode andcarry anodic or cathodic current. In some instances, an electrode mightbe an anode for a period of time and a cathode for a period of time.

Deep brain stimulation leads may include one or more sets of segmentedelectrodes. Segmented electrodes may provide for superior currentsteering than ring electrodes because target structures in deep brainstimulation are not typically symmetric about the axis of the distalelectrode array. Instead, a target may be located on one side of a planerunning through the axis of the lead. Through the use of a radiallysegmented electrode array (“RSEA”), current steering can be performednot only along a length of the lead but also around a circumference ofthe lead. This provides precise three-dimensional targeting and deliveryof the current stimulus to neural target tissue, while potentiallyavoiding stimulation of other tissue. Examples of leads with segmentedelectrodes include U.S. Pat. Nos. 8,473,061; 8,571,665; and 8,792,993;U.S. Patent Application Publications Nos. 2010/0268298; 2011/0005069;2011/0130803; 2011/0130816; 2011/0130817; 2011/0130818; 2011/0078900;2011/0238129; 2012/0016378; 2012/0046710; 2012/0071949; 2012/0165911;2012/197375; 2012/0203316; 2012/0203320; 2012/0203321; 2013/0197424;2013/0197602; 2014/0039587; 2014/0353001; 2014/0358208; 2014/0358209;2014/0358210; 2015/0045864; 2015/0066120; 2015/0018915; 2015/0051681;U.S. patent application Ser. Nos. 14/557,211 and 14/286,797; and U.S.Provisional Patent Application Ser. No. 62/113,291, all of which areincorporated herein by reference.

FIG. 3 illustrates one embodiment of a system for practicing theinvention. The system can include a computing device 300 or any othersimilar device that includes a processor 302 and a memory 304, a display306, an input device 308, and, optionally, an electrical stimulationsystem 312.

The computing device 300 can be a computer, tablet, mobile device, orany other suitable device for processing information. The computingdevice 300 can be local to the user or can include components that arenon-local to the computer including one or both of the processor 302 ormemory 304 (or portions thereof). For example, in at least someembodiments, the user may operate a terminal that is connected to anon-local computing device. In other embodiments, the memory can benon-local to the user.

The computing device 300 can utilize any suitable processor 302 and theterm “a processor” can include one or more hardware processors withinthe computing device or other components of the system or may be localto the user or non-local to the user or other components of thecomputing device. The processor 302 is configured to executeinstructions provided to the processor 302, as described below.

Any suitable memory 304 can be used for the computing device 302. Thememory 304 illustrates a type of computer-readable media, namelycomputer-readable storage media. Computer-readable storage media mayinclude, but is not limited to, nonvolatile, non-transitory, removable,and non-removable media implemented in any method or technology forstorage of information, such as computer readable instructions, datastructures, program modules, or other data. Examples ofcomputer-readable storage media include RAM, ROM, EEPROM, flash memory,or other memory technology, CD-ROM, digital versatile disks (“DVD”) orother optical storage, magnetic cassettes, magnetic tape, magnetic diskstorage or other magnetic storage devices, or any other medium which canbe used to store the desired information and which can be accessed by acomputing device.

Communication methods provide another type of computer readable media;namely communication media. Communication media typically embodiescomputer-readable instructions, data structures, program modules, orother data in a modulated data signal such as a carrier wave, datasignal, or other transport mechanism and include any informationdelivery media. The terms “modulated data signal,” and “carrier-wavesignal” includes a signal that has one or more of its characteristicsset or changed in such a manner as to encode information, instructions,data, and the like, in the signal. By way of example, communicationmedia includes wired media such as twisted pair, coaxial cable, fiberoptics, wave guides, and other wired media and wireless media such asacoustic, RF, infrared, and other wireless media.

The display 306 can be any suitable display device, such as a monitor,screen, display, or the like, and can include a printer. The inputdevice 308 can be, for example, a keyboard, mouse, touch screen, trackball, joystick, voice recognition system, or any combination thereof, orthe like.

The electrical stimulation system 312 can include, for example, any ofthe components illustrated in FIG. 1. The electrical stimulation system312 may communicate with the computing device 300 through a wired orwireless connection or, alternatively or additionally, a user canprovide information between the electrical stimulation system 312 andthe computing device 300 using a computer-readable medium or by someother mechanism. In at least some embodiments, the computing device 300may include part of the electrical stimulation system, such as, forexample, the IPG 14, CP 18, RC 16, ETS 20, or any combination thereof.

The methods and systems described herein may be embodied in manydifferent forms and should not be construed as limited to theembodiments set forth herein. Accordingly, the methods and systemsdescribed herein may take the form of an entirely hardware embodiment,an entirely software embodiment or an embodiment combining software andhardware aspects. Systems referenced herein typically include memory andtypically include methods for communication with other devices includingmobile devices. Methods of communication can include both wired andwireless (for example, RF, optical, or infrared) communications methodsand such methods provide another type of computer readable media; namelycommunication media. Wired communication can include communication overa twisted pair, coaxial cable, fiber optics, wave guides, or the like,or any combination thereof. Wireless communication can include RF,infrared, acoustic, near field communication, Bluetooth™, or the like,or any combination thereof.

During programming sessions, as well as at other times, it can behelpful to visualize the region that will be stimulated. Stimulationregion visualization systems and methods can be used to predict orestimate a region of stimulation for a given set of stimulationparameters. In at least some embodiments, the systems and methodsfurther permit a user to modify stimulation parameters and visuallyobserve how such modifications can change the predicted or estimatedstimulation region. Such algorithms and systems may provide greater easeof use and flexibility and may enable or enhance stimulation therapy.The terms “stimulation field map” (SFM), “volume of activation” (VOA),or “volume of tissue activated (VTA)” are often used to designate anestimated region of tissue that will be stimulated for a particular setof stimulation parameters. Any suitable method for determining theVOA/SFM/VTA can be used including those described in, for example, U.S.Pat. Nos. 8,326,433; 8,675,945; 8,831,731; 8,849,632; and 8,958,615;U.S. Patent Application Publications Nos. 2009/0287272; 2009/0287273;2012/0314924; 2013/0116744; 2014/0122379; and 2015/0066111; and U.S.Provisional Patent Application Ser. No. 62/030,655, all of which areincorporated herein by reference.

Existing VOA/SFM/VTA models are generally based on neural elements, suchas neural fibers, that are preferentially activated by cathodicstimulation (e.g., stimulation near a cathode). Anodic stimulation(e.g., stimulation near an anode) can activate different neuralelements. Moreover, the threshold for stimulation of many neuralelements is different for anodic and cathodic stimulation. As anexample, U.S. Pat. No. 6,560,490, incorporated herein by reference inits entirety, demonstrates in FIGS. 1 and 2 that cathodic stimulationactivates nerve fibers at much lower stimulation amplitudes thanneuronal cells. In contrast, anodic stimulation activates neuronal cellsat lower stimulation amplitudes than nerve fibers.

Because anodic stimulation activates neural elements differently fromcathodic stimulation, VOA/SFM/VTA models for cathodic stimulation willlikely be inaccurate in estimating the effect of anodic stimulation. Fora lead producing anodic stimulation or a combination of anodic andcathodic stimulation, it can be helpful to provide a system thatdisplays visualization of the anodic and cathodic stimulation regionsand conveys to a user which type of stimulation is being visualized.Alternatively, the visualization can be by neural element type, such asnerve fiber or neural cell or any other suitable selection of neuralelement type.

In many instances, for monopolar cathodic stimulation, the anode of theelectrical stimulation system is located on the case of the implantablepulse generator or at another site relatively distant from the cathodeor cathodes on the lead. Monopolar cathodic stimulation may also includeinstances where the anode is distributed over a large number of (forexample, at least four, five, six, seven, or more) electrodes on thelead or where the anode is positioned on the lead at a substantialdistance away from the cathode (for example, the anode is near theproximal end of the array of electrodes and the cathode is near theproximal end of the electrodes.) Similarly, monopolar anodic stimulationmay include instances where the cathode of the electrical stimulationsystem is located on the case of the implantable pulse generator or atanother site relatively distant from the anode or anodes on the lead orinstances where the cathode is distributed over a large number of (forexample, at least four, five, six, seven, or more) electrodes on thelead or where the cathode is positioned on the lead at a substantialdistance away from the anode (for example, the anode is near theproximal end of the array of electrodes and the cathode is near theproximal end of the electrodes.) Another method for identifying theanodic or cathodic nature of stimulation can be found in U.S. Pat. No.8,190,250, incorporated herein by reference in its entirety, whichobserves the angle of an electric field at particular points withrespect to the lead.

User interfaces can be provided to visualize anodic or cathodicstimulation or stimulation of nerve fibers, neural cells, or otherneural elements. Such user interfaces can be provided on the systemillustrated in FIG. 3, the CP 18 or RC 16 of FIG. 1, or any othersuitable system or device.

FIG. 4 illustrates one embodiment of a user interface 400 forvisualizing stimulation or for programming an electrical stimulationsystem. The user interface 400 includes a representation of a portion ofthe lead 406 with electrodes 408. In the illustrated example, electrode408 a is a cathode and electrode 408 b is an anode. It will beunderstood that any other electrode, or combination of electrodes, couldbe selected to be a cathode or anode. It will also be understood that insome embodiments, either the cathode or anode may be selected to be anelectrode that is distant from the illustrated portion of the lead (forexample, the housing of the implantable pulse generator.)

In FIG. 4, an estimated cathodic VOA (or VTA or SFM) 430 and anestimated anodic VOA (or VTA or SFM) 432 are illustrated. The lead 406,cathodic VOA 430, and anodic VOA 432 in the user interface 400 areillustrated in two dimensions. It will be understood, however, thatthese objects and VOAs are three-dimensional and, in some embodiments,may be displayed three-dimensionally or using perspective displaytechniques. In at least some embodiments, the user interface 400 caninclude controls for rotating the lead 406 and VOAs 430, 432 to showthese elements at different angles.

In the illustrated embodiment, the cathodic VOA 430 and anodic VOA aredistinguished using different types of cross-hatching. Other methods ofdistinguishing the VOAs 430, 432 can be used in combination with, or asan alternative to, cross-hatching including, but not limited to,different colors, different shading, different symbols, or the like, orany combination thereof. A legend 437 for the VOAs 430, 432 may beprovided.

In this embodiment, the anodic VOA 432 is illustrated in regions or atpoints where the nearest active electrode is an anode and the cathodicVOA 430 is illustrated in regions or at points where the nearest activeelectrode is a cathode. In the illustrated embodiment, there is oneanode and one cathode. In other instances, there may be more than oneanode or cathode. In such instances, the anodic or cathodic VOAcorresponding to the nearest anode or cathode will be displayed for eachparticular region or point. When there are multiple anodes or cathodes,in at least some embodiments, the anodic VOA 432 will represent all ofthe anodes and the cathodic VOA 430 will represent all of the cathodes.In other embodiments, a different anodic VOA 432 may be presented foreach of the anodes (or a subset of the anodes) and a different cathodicCTA 430 may be presented for each of the cathodes (or a subset of thecathodes). In such circumstances, the legend 437 and controls 436, 438for selecting which VOA to display modify, described below, may includeindividual controls for each of the different anodic and cathodic VOAs.

In this embodiment, the distances to the active electrodes (e.g., anodeand cathode) serve as a proxy for identifying which type of stimulation(anodic or cathodic) will be primarily present in a particular region orpoint. In other embodiments, other proxies may be used to determinewhether the anodic VOA or cathodic VOA will be displayed. For example,the distances may be weighted according to type of stimulation (forexample, cathodic stimulation may be weighted more heavily than anodicstimulation if cathodic stimulation is more effective for a givenstimulation amplitude), type of neural elements (for example, sometissue may be more receptive to cathodic stimulation than anodicstimulation), stimulation amplitude (for example, stimulation usingmultiple anodes or cathodes may result in different stimulationamplitudes for the active electrodes), or the like or any combinationthereof. In such embodiments, the anodic VOA 432 is displayed forregions or points where the weighted distance to the anode is greaterthan the weighted distance to the cathode and the cathodic VOA 430 isdisplayed for regions or points where the weighted distance to thecathode is greater than the weighted distance to the anode.

In other embodiments, as an alternative to, or in addition to,weighting, the proxy may be a non-linear function of the distance (forexample, a function of the distance squared or the square root of thedistance or a polynomial equation with the distance as a variable.)

The user interface 400 also includes one or more display controls 436for turning the display of the cathodic VOA 430 and anodic VOA 432 on oroff. In the illustrated embodiment, both the cathodic VOA 430 and anodicVOA 432 are displayed. Operation of the cathodic display control 436 acan remove display of the cathodic VOA 430. Similarly, operation of theanodic display control 436 b can remove display of the anodic VOA 432.In some embodiments, when one of the VOAs is removed, the other VOAremains, as illustrated in FIG. 4, limited to the region nearest thecorresponding electrode. In other embodiments, when one of the VOAs isremoved, the other VOA may be altered to show the entire shape of theVOA rather than being limited by the distances to the electrodes.

In at least some embodiments, the user interface 400 may includecontrols for modifying the VOAs 430, 432. Such controls can include aselection control 438 with individual controls 438 a, 438 b forselecting the cathodic VOA or anodic VOA. The controls can include movecontrols 440 to move the selected VOA up or down the lead or around thelead clockwise or counter-clockwise. The controls can include stretchcontrols 442 for stretching the selected VOA up or down the lead, awayfrom the lead, or around the lead in the clockwise or counter-clockwisedirection. The controls can include compress controls 442 forcompressing the selected VOA up or down the lead, toward from the lead,or inward from the clockwise or counter-clockwise direction. Any othersuitable modification controls can be included in the user interface.

In at least some embodiments, the system will determine, based on themodified VOA, changes to the stimulation parameters to approximate themodified VOA. Such changes may include, for example, changing theelectrode selection or the stimulation amplitude. As an example, movingor stretching the VOA up or down the lead may include shifting some orall of the stimulation to another electrode (or electrodes) further upor down the lead. As another example, stretching the VOA away from thelead may include increasing the stimulation amplitude.

FIG. 5 illustrates another embodiment of a user interface 500 forvisualizing stimulation or for programming an electrical stimulationsystem. The user interface 500 includes a representation of a portion ofthe lead 406 with electrodes 408. In the illustrated example, electrode408 a is a cathode and electrode 408 b is an anode. In FIG. 5, anestimated cathodic VOA 430 and an estimated anodic VOA 432 areillustrated including a region 434 where the cathodic VOA 430 and theanodic VOA 432 overlap. The user interface also includes the displaycontrols 436, selection control 438, move controls 440, stretch controls442, and compress controls 444 described above.

FIG. 6 illustrates another embodiment of a user interface 600 forvisualizing stimulation or for programming an electrical stimulationsystem. The user interface 600 includes a representation of a portion ofthe lead 406 with electrodes 408. In the illustrated example, electrode408 a is a cathode and electrode 408 b is an anode. In FIG. 6, anestimated fiber VOA 431 and an estimated cell VOA 433 are illustratedincluding a region 435 where the fiber VOA 431 and the cell VOA 433overlap. As discussed above, it is found that cathodic stimulationpreferentially stimulates fibers, but does provide some stimulation ofneural cells. Conversely, anodic stimulation preferentially stimulatesneural cells, but also stimulates fibers. Accordingly, the combinationof anodic and cathodic stimulation will stimulate both fibers and neuralcells, but in different and overlapping regions. In at least someembodiments, the determination of the fiber VOA 431 is at leastpartially based on a second difference of the scalar potential (forexample, an activating function, derivative of the E field, orderivative of the J field.) In at least some embodiments, thedetermination of the cell VOA 433 is at least partially based on a firstdifference of the scalar potential (e.g., the E field or the J field.)

In other embodiments, similar to the user interface of FIG. 6, differenttypes of neural elements can be selected for displayable VOAs. Forexample, large fibers, small fibers, fibers or cells oriented parallelto the lead, fibers or cells oriented perpendicular to the lead, fibersor cells oriented in a particular angular range relative to the lead,specific types of neural cells, neuron terminals, synapses, neurons withdifferent biophysical properties (such as specific ion channelproperties), or the like, or any combination thereof. In at least someembodiments, the user interface can display VOAs for two, three, four,or more different types of neural elements. In at least someembodiments, the VOAs can be determined using monopolar cathodicstimulation, monopolar anodic stimulation, or bipolar/multipolarstimulation.

The user interface also includes the display controls 436, selectioncontrol 438, move controls 440, stretch controls 442, and compresscontrols 444 described above. These controls, however, are now directedto displaying or modifying the fiber VOA 431 or cell VOA 433.

FIG. 7 illustrates another embodiment of a user interface 700 forvisualizing stimulation or for programming an electrical stimulationsystem. The user interface 700 includes a representation of a portion ofthe lead 406 with electrodes 408. In the illustrated example, electrode408 a is a cathode and electrode 408 b is an anode. In FIG. 7, a set ofestimated fiber VOA contour lines 441 and a set of estimated cell VOAcontour lines 443. In another embodiment, contour lines for anodic andcathodic VOAs (see, FIGS. 4 and 5) can be displayed. Each contour lineof a set corresponds to a different stimulation amplitude. In otherembodiments, the contour lines can correspond to changing otherstimulation parameters, such as electrode selection, pulse width, pulseduration, or the like, or any combination thereof. In anotherembodiment, instead of contour lines, a map of the region around thelead can be displayed with shading or coloring that varies according tothe stimulation amplitude that is needed to stimulate the region. Forexample, shading can be darkest for lower amplitude and become lighterfor higher amplitude or coloring can range from blue for lower amplitudeto red for higher amplitude.

The user interface also includes the display controls 436, selectioncontrol 438, move controls 440, stretch controls 442, and compresscontrols 444 described above. These controls, however, are now directedto displaying or modifying the fiber VOA contour lines 441 or cell VOAcontour lines 443.

FIG. 8 illustrates another embodiment of a user interface 800 forvisualizing stimulation or for programming an electrical stimulationsystem. The user interface 800 includes a representation of a portion ofthe lead 406 with electrodes 408. In the illustrated example, electrode408 a is a cathode and electrode 408 b is an anode. In FIG. 8, insteadof illustrating VOAs, anatomical elements (such as previously identifiedanatomical structures) are illustrated and are marked based on whether athreshold amount of the particular anatomical element is stimulated bythe anode or cathode or not stimulated. In the illustrated embodiments,anatomical element 445 is stimulated by the cathode, anatomical element447 is stimulated by the anode, and anatomical element is notstimulated. In at least some embodiments, the amount of an anatomicalstructure that is stimulated is determined using the VOAs describedabove. In at least some embodiments, a user can set the threshold amountfor all anatomical elements. In at least some embodiments, a user canset the threshold amount individually for each anatomical element orsubset of anatomical elements.

The user interface also includes the display controls 436, selectioncontrol 438, move controls 440, stretch controls 442, and compresscontrols 444 described above.

When the display or modify controls are operated, the markings on theanatomical elements will be modified based on the modifications to thecathode or anode VOAs.

In at least some embodiments, any combination of the VOAs and otherelements described above for the interfaces illustrated in FIGS. 4 to 8can be used. In at least some embodiments, multiple VOAs determinedusing different stimulation conditions or different types of stimulationcan be used. For example, any combination of cathodic VOAs, anodic VOAs,fiber VOAs, cell VOAs, terminal VOAs, or the like can be displayedsimultaneously or sequentially. Providing these different VOAs can allowa user to compare the stimulation for different conditions. In at leastsome embodiments, a current, most recent, or user-selected VOA may behighlighted (using, for example, a different color, bold colors orboundaries or contour lines, or shading).

In at least some embodiments, the user can select a time varyingstimulation (for example, stimulation that varies from cathodic toanodic stimulation). Any of the user interfaces described above mayinclude controls for defining the time variation. Any of the userinterfaces described above may also include controls that provide ananimation of the resulting time-varying VOA. For example, an animatedtime-varying VOA may transition from anodic to cathodic stimulation (orvice versa). The location of the time-varying VOA may remain constant ormay shift over time.

FIG. 9 is a flowchart of one embodiment of a method of visualizingstimulation or for programming an electrical stimulation system. In step902, a set of stimulation parameters is received including a selectionof at least one anode and at least one cathode. In step 904, cathodicand anodic VOAs are obtained. The system may calculate the VOAs or mayreceive the VOAs from another system or may determine the VOAs fromlook-up tables, databases, or the like or may obtain the VOAs in anyother suitable manner.

In step 906, the system displays the electrodes, cathodic VOA, andanodic VOA. For example, any of the user interfaces described above(including, but not limited to the user interfaces illustrated in FIGS.4 and 5) can be used for displaying these elements. In step 908,modification controls, such as those illustrated in FIGS. 4 and 5, aredisplayed. In step 910, when the cathodic or anodic VOA is modifiedusing the modification controls, the system determines a modified set ofstimulation parameters that will approximate the modified VOA. Inoptional step 912, a selection of one set of stimulation parameters isreceived and the system sends the selected set of stimulation parametersto an implantable pulse generator (or other device) to providestimulation to a patient using the selected stimulation parameters.

FIG. 10 is a flowchart of another embodiment of a method of visualizingstimulation or for programming an electrical stimulation system. In step1002, a set of stimulation parameters is received including a selectionof at least one anode and at least one cathode. In step 1004, fiber andcell VOAs are obtained. The system may calculate the VOAs or may receivethe VOAs from another system or may determine the VOAs from look-uptables, databases, or the like or may obtain the VOAs in any othersuitable manner.

In step 1006, the system displays the electrodes, fiber VOA, and cellVOA. For example, any of the user interfaces described above (including,but not limited to the user interfaces illustrated in FIGS. 6 and 7) canbe used for displaying these elements. In step 1008, modificationcontrols, such as those illustrated in FIGS. 6 and 7, are displayed. Instep 1010, when the fiber or cell VOA is modified using the modificationcontrols, the system determines a modified set of stimulation parametersthat will approximate the modified VOA. In optional step 1012, aselection of one set of stimulation parameters is received and thesystem sends the selected set of stimulation parameters to animplantable pulse generator (or other device) to provide stimulation toa patient using the selected stimulation parameters.

FIG. 11 is a flowchart of one embodiment of a method of visualizingstimulation or for programming an electrical stimulation system. In step1102, a set of stimulation parameters is received including a selectionof at least one anode and at least one cathode. Also, a set ofanatomical elements is received. In step 1104, the system determineswhich of the anatomical elements are stimulated, by a threshold amount,by cathodic or anodic stimulation. For example, the system may obtainthe cathodic and anodic VOAs and determine which of the anatomicalelements have a threshold amount within the respective VOAs.

In step 1106, the system displays the electrodes and anatomical elementsindicating which of the anatomical elements are activated by a thresholdamount by cathodic stimulation, which of the anatomical elements areactivated by a threshold amount by anodic stimulation, and which of theanatomical elements are not activated. For example, any of the userinterfaces described above (including, but not limited to the userinterface illustrated in FIG. 8) can be used for displaying theseelements. In step 1108, modification controls, such as those illustratedin FIG. 8, are displayed. In step 1110, when the cathodic or anodic VOAis modified using the modification controls, the system determines amodified set of stimulation parameters that will approximate themodified VOA. In optional step 1112, a selection of one set ofstimulation parameters is received and the system sends the selected setof stimulation parameters to an implantable pulse generator (or otherdevice) to provide stimulation to a patient using the selectedstimulation parameters.

It will be understood that the system can include one or more of themethods described hereinabove with respect to FIGS. 9-11 in anycombination. The methods, systems, and units described herein may beembodied in many different forms and should not be construed as limitedto the embodiments set forth herein. Accordingly, the methods, systems,and units described herein may take the form of an entirely hardwareembodiment, an entirely software embodiment or an embodiment combiningsoftware and hardware aspects. The methods described herein can beperformed using any type of processor or any combination of processorswhere each processor performs at least part of the process.

It will be understood that each block of the flowchart illustrations,and combinations of blocks in the flowchart illustrations and methodsdisclosed herein, can be implemented by computer program instructions.These program instructions may be provided to a processor to produce amachine, such that the instructions, which execute on the processor,create means for implementing the actions specified in the flowchartblock or blocks disclosed herein. The computer program instructions maybe executed by a processor to cause a series of operational steps to beperformed by the processor to produce a computer implemented process.The computer program instructions may also cause at least some of theoperational steps to be performed in parallel. Moreover, some of thesteps may also be performed across more than one processor, such asmight arise in a multi-processor computer system. In addition, one ormore processes may also be performed concurrently with other processes,or even in a different sequence than illustrated without departing fromthe scope or spirit of the invention.

The computer program instructions can be stored on any suitablecomputer-readable medium including, but not limited to, RAM, ROM,EEPROM, flash memory or other memory technology, CD-ROM, digitalversatile disks (“DVD”) or other optical storage, magnetic cassettes,magnetic tape, magnetic disk storage or other magnetic storage devices,or any other medium which can be used to store the desired informationand which can be accessed by a computing device.

The above specification provides a description of the structure,manufacture, and use of the invention. Since many embodiments of theinvention can be made without departing from the spirit and scope of theinvention, the invention also resides in the claims hereinafterappended.

What is claimed as new and desired to be protected by Letters Patent ofthe United States is:
 1. A method for programming electrical stimulationof a patient using an implantable electrical stimulation systemincluding an implantable pulse generator and a lead having a pluralityof electrodes, the method comprising: obtaining a cathodic volume ofactivation (“VOA”) for monopolar cathodic stimulation using at least onecathode, wherein the cathodic VOA is an estimated volume of tissueactivated by the at least one cathode using a set of stimulationparameters; obtaining an anodic VOA for monopolar anodic stimulationusing at least one anode, wherein the anodic VOA is an estimated volumeof tissue activated by the at least one anode using the set ofstimulation parameters; displaying, on a display, a graphicalrepresentation of the electrodes, a graphical representation of thecathodic VOA, and a graphical representation the anodic VOA; when thecathodic VOA or anodic VOA is modified using modification controls,modifying the graphical representation of the cathodic VOA or thegraphical representation of the anodic VOA and determining a modifiedset of stimulation parameters corresponding to the modified graphicalrepresentation of the cathodic VOA or the modified graphicalrepresentation of the anodic VOA; programming the implantable pulsegenerator with the set of stimulation parameters or the modified set ofstimulation parameters; and electrically stimulating the patientaccording to the set of stimulation parameters or the modified set ofstimulation parameters using the implantable pulse generator and theelectrodes of the lead.
 2. The method of claim 1, further comprisingdisplaying controls, on the display, for turning off the displaying ofthe graphical representation of the cathodic VOA or the graphicalrepresentation of the anodic VOA.
 3. The method of claim 1, whereindisplaying the graphical representation of the cathodic VOA and thegraphical representation of the anodic VOA comprises displaying, on thedisplay, the graphical representation of the cathodic VOA for regionsthat are closer to any one of the at least one cathode than to any oneof the at least one anode and displaying, on the display, the graphicalrepresentation of the anodic VOA for regions that are closer to any oneof the at least one anode than to any one of the at least one cathode.4. The method of claim 1, wherein displaying the graphicalrepresentation of the cathodic VOA and the graphical representation ofthe anodic VOA comprises using different graphical features todistinguish the graphical representation of the cathodic VOA and thegraphical representation of the anodic VOA.
 5. The method of claim 4,wherein using different graphical features comprises using a thirdgraphical feature for any region in which the cathodic VOA overlaps theanodic VOA.
 6. The method of claim 1, wherein the modification controlscomprise move, stretch, or compress controls to move, stretch, orcompress the cathodic VOA or the anodic VOA relative to the lead.
 7. Themethod of claim 1, further comprising displaying, on the display, acontrol for presenting an animation of the cathodic VOA or the anodicVOA for a time-varying stimulation.
 8. The method of claim 1, whereinobtaining the cathodic VOA comprises obtaining cathodic VOAs formonopolar cathodic stimulation using a plurality of different sets ofstimulation parameters; obtaining the anodic VOA comprises obtaininganodic VOAs for monopolar anodic stimulation using the plurality ofdifferent sets of stimulation parameters; and displaying the graphicalrepresentation of the cathodic VOA and the graphical representation ofthe anodic VOA comprises displaying, on the display, the graphicalrepresentations of the cathodic VOAs as a set of contour lines and thegraphical representations of the anodic VOAs as a set of contour lines.9. The method of claim 1, wherein obtaining the cathodic VOA comprisesobtaining cathodic VOAs for monopolar cathodic stimulation using aplurality of different sets of stimulation parameters; obtaining theanodic VOA comprises obtaining anodic VOAs for monopolar anodicstimulation using the plurality of different sets of stimulationparameters; and displaying the graphical representation of the cathodicVOA and the graphical representation of the anodic VOA comprisesdisplaying, on the display, the graphical representations of thecathodic VOAs using a first variation in shading or color and thegraphical representations of the anodic VOAs using a second variation inshading or color.
 10. A non-transitory computer-readable medium havingcomputer executable instructions stored thereon that, when executed by aprocessor, cause the processor to perform actions for programmingelectrical stimulation of a patient using an implantable electricalstimulation system including an implantable pulse generator and a leadhaving a plurality of electrodes, the actions comprising: obtaining acathodic volume of activation (“VOA”) for monopolar cathodic stimulationusing at least one cathode, wherein the cathodic VOA is an estimatedvolume of tissue activated by the at least one cathode using a set ofstimulation parameters; obtaining an anodic VOA for monopolar anodicstimulation using at least one anode, wherein the anodic VOA is anestimated volume of tissue activated by the at least one anode using theset of stimulation parameters; displaying, on a display, a graphicalrepresentation of the electrodes, a graphical representation of thecathodic VOA, and a graphical representation the anodic VOA; when thecathodic VOA or anodic VOA is modified using modification controls,modifying the graphical representation of the cathodic VOA or thegraphical representation of the anodic VOA and determining a modifiedset of stimulation parameters corresponding to the modified graphicalrepresentation of the cathodic VOA or the modified graphicalrepresentation of the anodic VOA; and initiating a signal that providesthe implantable pulse generator of the electrical stimulation systemwith the set of stimulation parameters or the modified set ofstimulation parameters for generating electrical stimulation for thepatient through the electrodes of the lead.
 11. The non-transitorycomputer-readable medium of claim 10, the actions further comprisingdisplaying controls, on the display, for turning off the displaying ofthe graphical representation of the cathodic VOA or the graphicalrepresentation of the anodic VOA.
 12. The non-transitorycomputer-readable medium of claim 10, wherein displaying the graphicalrepresentation of the cathodic VOA and the graphical representation ofthe anodic VOA comprises displaying, on the display, the graphicalrepresentation of the cathodic VOA for regions that are closer to anyone of the at least one cathode than to any one of the at least oneanode and displaying, on the display, the graphical representation ofthe anodic VOA for regions that are closer to any one of the at leastone anode than to any one of the at least one cathode.
 13. Thenon-transitory computer-readable medium of claim 10, wherein displayingthe graphical representation of the cathodic VOA and the graphicalrepresentation of the anodic VOA comprises using different graphicalfeatures to distinguish the graphical representation of the cathodic VOAand the graphical representation of the anodic VOA.
 14. Thenon-transitory computer-readable medium of claim 13, wherein usingdifferent graphical features comprises using a third graphical featurefor any region in which the cathodic VOA overlaps the anodic VOA. 15.The non-transitory computer-readable medium of claim 10, wherein themodification controls comprise move, stretch, or compress controls tomove, stretch, or compress the cathodic VOA or the anodic VOA relativeto the lead.
 16. The non-transitory computer-readable medium of claim10, the actions further comprising displaying, on the display, a controlfor presenting an animation of the cathodic VOA or the anodic VOA for atime-varying stimulation.
 17. The non-transitory computer-readablemedium of claim 10, wherein obtaining the cathodic VOA comprisesobtaining cathodic VOAs for monopolar cathodic stimulation using aplurality of different sets of stimulation parameters; obtaining theanodic VOA comprises obtaining anodic VOAs for monopolar anodicstimulation using the plurality of different sets of stimulationparameters; and displaying the graphical representation of the cathodicVOA and the graphical representation of the anodic VOA comprisesdisplaying, on the display, the graphical representations of thecathodic VOAs as a set of contour lines and the graphicalrepresentations of the anodic VOAs as a set of contour lines.
 18. Thenon-transitory computer-readable medium of claim 10, wherein obtainingthe cathodic VOA comprises obtaining cathodic VOAs for monopolarcathodic stimulation using a plurality of different sets of stimulationparameters; obtaining the anodic VOA comprises obtaining anodic VOAs formonopolar anodic stimulation using the plurality of different sets ofstimulation parameters; and displaying the graphical representation ofthe cathodic VOA and the graphical representation of the anodic VOAcomprises displaying, on the display, the graphical representations ofthe cathodic VOAs using a first variation in shading or color and thegraphical representations of the anodic VOAs using a second variation inshading or color.
 19. A method for programming electrical stimulation ofa patient using an implantable electrical stimulation system includingan implantable pulse generator and a lead having a plurality ofelectrodes, the method comprising: determining which of a plurality ofanatomical elements are activated by a threshold amount by monopolarcathodic stimulation using a set of stimulation parameters; determiningwhich of the plurality of anatomical elements are activated by athreshold amount by monopolar anodic stimulation using the set ofstimulation parameters; displaying, on a display, a graphicalrepresentation of the electrodes and a graphical representation of theanatomical elements, indicating which of the anatomical elements areactivated by a threshold amount by the monopolar cathodic stimulation,which of the anatomical elements are activated by a threshold amount bythe monopolar anodic stimulation, and which of the anatomical elementsare not activated; when the set of stimulation parameters is modifiedusing modification controls, determining which of the anatomicalelements are activated by a threshold amount by the monopolar cathodicstimulation or the monopolar anodic stimulation using the modified setof stimulation parameters and modifying the graphical representations ofthe anatomical elements; programming the implantable pulse generatorwith the set of stimulation parameters or the modified set ofstimulation parameters; and electrically stimulating the patientaccording to the set of stimulation parameters or the modified set ofstimulation parameters using the implantable pulse generator and theelectrodes of the lead.
 20. The system of claim 19, wherein displayingthe graphical representation of the anatomical elements comprises usingdifferent graphical features to distinguish the graphical representationof the anatomical elements activated by the monopolar cathodicstimulation and the graphical representation of the anatomical elementsactivated by the monopolar anodic stimulation.